266261 has 2 divisors, whose sum is σ = 266262. Its totient is φ = 266260.

The previous prime is 266239. The next prime is 266269. The reversal of 266261 is 162662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 255025 + 11236 = 505^2 + 106^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-266261 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 266261.

It is not a weakly prime, because it can be changed into another prime (266269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133130 + 133131.

It is an arithmetic number, because the mean of its divisors is an integer number (133131).

2²⁶⁶²⁶¹ is an apocalyptic number.

It is an amenable number.

266261 is a deficient number, since it is larger than the sum of its proper divisors (1).

266261 is an equidigital number, since it uses as much as digits as its factorization.

266261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 23.

The square root of 266261 is about 516.0048449385. The cubic root of 266261 is about 64.3333035040. Note that the first 4 decimals are identical.

The spelling of 266261 in words is "two hundred sixty-six thousand, two hundred sixty-one".